1 files changed, 39 insertions, 9 deletions
diff --git a/src/main/java/org/traccar/helper/BufferUtil.java b/src/main/java/org/traccar/helper/BufferUtil.java
index 9485c17c6..12c31ba9d 100644
--- a/src/main/java/org/traccar/helper/BufferUtil.java
+++ b/src/main/java/org/traccar/helper/BufferUtil.java
@@ -27,6 +27,24 @@ public final class BufferUtil {
     private BufferUtil() {
     }
 
+    public static int readSignedMagnitudeInt(ByteBuf buffer) {
+        long value = buffer.readUnsignedInt();
+        int result = (int) BitUtil.to(value, 31);
+        return BitUtil.check(value, 31) ? -result : result;
+    }
+
+    public static int indexOf(ByteBuf buffer, int fromIndex, int toIndex, byte value, int count) {
+        int startIndex = fromIndex;
+        for (int i = 0; i < count; i++) {
+            int result = buffer.indexOf(startIndex, toIndex, value);
+            if (result < 0 || i == count - 1) {
+                return result;
+            }
+            startIndex = result + 1;
+        }
+        return -1;
+    }
+
     public static int indexOf(String needle, ByteBuf haystack) {
         return indexOf(needle, haystack, haystack.readerIndex(), haystack.writerIndex());
     }
@@ -41,16 +59,28 @@ public final class BufferUtil {
     }
 
     public static int indexOf(ByteBuf needle, ByteBuf haystack, int startIndex, int endIndex) {
-        ByteBuf wrappedHaystack;
-        if (startIndex == haystack.readerIndex() && endIndex == haystack.writerIndex()) {
-            wrappedHaystack = haystack;
-        } else {
-            wrappedHaystack = Unpooled.wrappedBuffer(haystack);
-            wrappedHaystack.readerIndex(startIndex - haystack.readerIndex());
-            wrappedHaystack.writerIndex(endIndex - haystack.readerIndex());
+        int originalReaderIndex = haystack.readerIndex();
+        int originalWriterIndex = haystack.writerIndex();
+        try {
+            haystack.readerIndex(startIndex);
+            haystack.writerIndex(endIndex);
+            return ByteBufUtil.indexOf(needle, haystack);
+        } finally {
+            haystack.readerIndex(originalReaderIndex);
+            haystack.writerIndex(originalWriterIndex);
+        }
+    }
+
+    public static boolean isPrintable(ByteBuf buf, int length) {
+        boolean printable = true;
+        for (int i = 0; i < length; i++) {
+            byte b = buf.getByte(buf.readerIndex() + i);
+            if (b < 32 && b != '\r' && b != '\n') {
+                printable = false;
+                break;
+            }
         }
-        int result = ByteBufUtil.indexOf(needle, wrappedHaystack);
-        return result < 0 ? result : startIndex + result;
+        return printable;
     }
 
 }